Coated abrasive wheel for polishing concave surfaces



IN VEN TORS RUSSELL W. BERNSTEIN ALECK BLOCK .I .......n l...

and

THEIR ATTORNEY Sept. 3, l1957 R. W. BERNSTEIN ET AL COATED ABRASIVE WHEEL FOR POLISHING CONCAVE SURFACES Filed Oct. l0, 1955 COATED ABRASIVE WHEEL FOR POLISHING CONCAVE SACES Russell W. Bernstein, Los Angeles, and Aleck Block, Culver City, Calif.

Application October 10, 1955, Serial No. 539,622

7 Claims. (Cl. 51-194) This invention relates to a coated abrasive wheel for polishing or light grinding of concave surfaces.

It is an object of our invention to provide a new and improved wheel of the class described, which can be formed with substantially any diameter and radius, including extremely small radii.

In essence, our invention contemplates a device of the class described which comprises a central circular member, around the outer periphery of which extend a plurality of overlapping segments of abrasive coated material. The ends of the segments are attached to the sides of the circular member and in use are further clamped and held by rigid or semi-rigid side flanges. The abrasive segments may be disposed around a resilient member which permits them to conform, to a certain extent, to the surface being polished.

It is an object of our invention to provide an improved abrasive wheel of the type described above. It is a further object of our invention to provide such a wheel in which the segments overlap each other a substantial amount, so that as the exposed portions become worn, new abrasive is exposed from the portion of the adjacent segment disposed therebeneath, thus providing fresh abrasive and extending the life of the wheel.

It is a further object of our invention to provide such a wheel in which the use of segments of abrasive material extending substantially transversely to the periphery of the wheel permits the formation of an abrasive wheel having a small radius without buckling or folding of the abrasive material.

Another object of our invention is to provide a Wheel of the type described which is light in Weight, simple and economical to manufacture and easy to replace when it has become worn. it is among the further objects of our invention to provide such a wheel which is sturdy in construction and in which the abrasive segments will not become separated from the Wheel in use.

Our invention also comprises such other objects, advantages and capabilities as will later more fully appear and which are inherently possessed by our invention.

While we have shown in the accompanying drawings preferred embodiments of our invention, it should be understood that the same are susceptible of modification and change without departing from the spirit of the invention.

Referring to the drawings, Fig. 1 is a side elevational view of a preferred embodiment of our abrasive wheel;

Fig. 2 is a sectional view of the same, taken on line 2 2 of Fig. l;

Fig. 3 is an enlarged view showing the abrasive segments and rope strands;

Fig. 4 is a side elevational view of the rope strands and abrasive segments;

Fig. 5 is an enlarged sectional view of the peripheral portion of another embodiment of our abrasive wheel.

A preferred embodiment which has been selected to illustrate our invention comprises a central circular member 19, which is preferably formed of substantially rigid ri 2,84,73l EC@ Patented Sept. 3, 1957 material such as cardboard or the like. The circular member 10 is provided with a centrally disposed circular opening 11.

The abrasive portion of our device is preferably formed by utilizing a plurality of small segments 12 of cloth or paper, which is coated on one side thereof with suitable abrasive material. The segments 12 are substantially rectangular in shape and are aligned so that each segment overlaps substantially half of the adjacent segment.

The method of manufacture used to form our wheel may vary considerably. One example is as follows: A pair of elongated pieces of soft cotton rope 13 are placed a slight distance apart from each other and adhered to the non-abrasive coated sides of the segments 12 adjacent the mid-portion thereof. A length of the abrasive assembly so formed is then placed around the peripheral edge of the circular member 10 and adhered thereto. The glue or other adhesive material preferably extends inwardly from the edge of the circular member 10, so that the ropes 13 are adhered to the opposite sides of the circular member 10 adjacent the peripheral edge thereof and the ends of the segments 12 are adhered to the sides of the circular member 10.

The segments 12 have a certain degree of stiffness, so that they extend across the ropes 13 to provide a substantially circular small resilient edge extending around the entire periphery of the circular member lil. This curved resilient abrasive surface is adapted for use in polishing a concave surface. As the wheel contacts the work surface, the resilient backing provided by the rope 13 permits the wheel to conform to a certain extent, to the contour of the work surface.

A pair of side pieces 14 of cardboard or the like are adhered to the opposite sides of circular member 10, extending over the ends of segments 12 to provide a iinished appearance for the wheel. This completes the abrasive wheel itself, which may be shipped and handled as a complete unit.

In use, our wheel is mounted between a pair of rigid circular side anges 15, which are preferably formed of metal. The flanges 15 are provided with centrally disposed openings. A circular shaft 17 extends through the openings in flanges 15 into opening 11 in circular member 10. The end of the shaft 17 is screw threaded and carries a nut 18. The side flanges 15 are clamped'tightly against the sides of the abrasive wheel so that their outer edge portions overlap the Vends of the abrasive segments 12. The opposite ends of each of the segments are thus clamped tightly in place to prevent separation of the segments from the wheel in use. The shaft 17 may be suitably attached to a source of rotation.

In use, the entire periphery of the Wheel presents a continuous substantially resilient convex surface. As the abrasive segments 12 become worn through use, portions of the adjacent segments therebeneath become exposed, so that fresh abrasive is always present and the life of the wheel is doubled. When the abrasive segments 12 are completely worn away, the wheel is easily replaced.

Another embodiment of our invention, which is shown in Fig. 5 of the drawings, is formed in a similar manner, except that a piece of resilient tubing 19 is slit longi tudinally and mounted on the peripheral edge of circular member 10. The abrasive segments 12 extend around the tube 19, with their ends being adhered to the sides of the circular member 1i).

In addition to the structures shown and described, our invention contemplates the use of any rounded or convex substantially resilient surface formed in any suitable manner around the entire outer` edge of the wheel, with the abrasive strips extending across and being disposed closely adjacent thereto around the entire periphery of the Wheel.

resilient backing material may be omitted, with the abrasive strips extending directly across the periphery f the Wheel.

With regard to the side flanges IS', these provide sun-"1- cient rigidity so that the exposed sides of the abrasive segments 12 can be used to contact' the Work surface. Toward this end, the side anges maybe formed of semirigid materials to permit slight bending ofthe Wheel in use.

In case a sharp abrasive isused, additionalsegments of non-abrasive material may be interposed between the abrasive segments 12 to prevent the abrasive on one'- segment from Wearing throughf the bottom of the segment disposed thereabove. f Y i g l It will be noted that the entire area of the segments isheld closely adjacent tothe periphery of 4the Wheel, so that noy Whipping or flapping action occurs; There is no play or loose area between the abrasive segments and the wheel.

We claim:

1. An abrasive wheel comprising. a cardboard circular member having a centrally disposed opening extending therethrough, a plurality ofl substantially rectangular seg'-v ments coated with abrasive material on the outer sides thereof, said segments being disposed so that each speg-y ment overlaps substantially half of the adjacent segment, a pair of lengths of cotton rope adhered to the inner sides' of said segments adjacent and on opposite sides' of the mid-portion thereof, said lengths of rope being adhered to the peripheral edge of saidV circular member, with said segments extending transversely thereacross, the ends of said segments being adhered to the opposite sides ofl said circular member, said ropes and abrasive segments extending around the entire peripheral edge of said circular member to provide a rounded resilient surface, and'a pair` of side pieces adhered tothe sides of said circular mem'- ber overlying the ends of said abrasive segments.

2. An abrasive wheel comprising a cardboard circular member having a centrally disposed opening. extending. therethrough, a plurality of substantially rectangular segments` coated with abrasive material on the' outer sides thereof, said segments being disposed so that each seg'- ment overlaps substantially half of the adjacent segment, and a pair of lengths of cotton ropev adhered to the inner sides of said segments.

3. The subject matter of claimr 2' and' a pair of` substantially rigid circular side anges' disposed. on opposite sides of said wheel, the edge portions of saidY flanges overlying and adapted to clamp between' them they opposite 4 endA portions of eachoi said abrasive segments to prevent separation of said segments from the wheel.

4. An abrasive wheel comprising a substantially rigid circular member, a plurality of segments coated with abrasive material on the outer Sides thereof, said segments being disposed so that each segment overlaps substantially half of the( adjacent segment, and a substantially resilient member mounted around the entire peripheral edge of said circular member, said abrasive segments extending transversely thereacross, the ends of said segments being adhered to the opposite sides of said circular member, the midportions of said segments being held closely adjacent to the circumference of said resilient member to provide a substantially resilient abrasive surface around the entire peripheral edge of said circular member, each of said segments upon being Worn exposing the portion of the adjacent abrasive segment disposed therebeneath.

S. An abrasive Wheel comprising a substantially rigid circular member, av plurality of segmentscoated with abrasive materi'al on the outer sides thereof, and a substantially resilient member mounted around the Ventire peripheral edge of said circular member, said abrasive Seg-Y ments extending transversely thereacross, the ends of said segments'- lfn'eilngv adhered to the opposite sides of said circular member, the Amidportion of saidsegments being held closely adjacent to the circumference of said resilient member to-'pxfovidea substantially resilient surface aroundy the entire peripheral edge of said circular member.

'6; An abrasive Wheel comprising a circular member havin'gl a convex peripheral edge, and 4a plurality of segments coated with abrasive material onV the outer sides thereof, sia-id segments extending transversely acrossV and closely adjacent to the peripheral edge of said circular member to provide a convex abrasive surface extending around'- the entire peripheral edge of said wheel.

.7. The subject matter of claim 6 anda pair of substan tially' rigid circular side flanges disposedlonopposite sides of said Wheel, the* edge portions of said anges overlying and adapted to clamp between them thel opposite end portions of each of said abrasive segments to prevent separation of said segments from the wheel.

References Cited in the le of thispat'ent UNITED STATES PATENTS 233,211 Crooker Oct. 12, 1880 837,556 Fryer Dec. 4, 1906` 1,377,598 Paoli May l0; 1921 1,869,564 Johnston Aug. 2, 1932 2,447,748 Graham Aug. 24, 1948 

